Catalog and Directory

The DB2 catalog and directory act as central repositories for all information about the support and operations of DB2 objects, authorizations, and communications. The catalog comprises several DB2 tables and can be accessed via SQL. The catalog contains details about DB2 objects obtained from the DDL (Data Definition Language) when an object is created or altered or from DCL (Data Control Language) when an authorization is granted on an object or a group of objects. The DB2 catalog also contains information about communications with other DB2 and non-DB2 databases through the use of the communications database (CDB), which contains information about VTAM and TCP/IP addresses.

Table 2-4 lists the DB2 catalog tables and the types of information in each. (Descriptions of all the columns in the DB2 catalog tables can be found in detail in Appendix D of the IBM DB2 for z/OS Version 8 SQL Reference Manual.)

Table 2-4. DB2 Catalog Tables

Table Name (SYSIBM.table)	Information Contents
IPLIST	Allows multiple IP addresses to be specified for a given LOCATION. Insert rows into this table when you want to define a remote DB2 data sharing group. Rows can be inserted, updated, and deleted.
IPNAMES	Defines the remote DRDA servers DB2 can access using TCP/IP. Rows in this table can be inserted, updated, and deleted.
LOCATIONS	Contains a row for every accessible remote server. The row associates a LOCATION name with the TCP/IP or SNA network attributes for the remote server. Requesters are not defined in this table. Rows in this table can be inserted, updated, and deleted.
LULIST	Allows multiple LU (Logical Unit) names to be specified for a given LOCATION. Insert rows into this table when you want to define a remote DB2 data sharing group. The same value for the LUNAME column cannot appear in both the SYSIBM.LUNAMES table and the SYSIBM.LULIST table. Rows in this table can be inserted, updated, and deleted.
LUMODES	Each row of the table provides VTAM with conversation limits for a specific combination of LUNAME and MODENAME. The table is accessed only during the initial conversation-limit negotiation between DB2 and a remote LU. This negotiation is called change-number-of-sessions (CNOS) processing. Rows in this table can be inserted, updated, and deleted.
LUNAMES	The table must contain a row for each remote SNA client or server that communicates with DB2. Rows can be inserted, updated, or deleted.
MODESELECT	Associates a mode name with any conversation created to support an outgoing SQL request. Each row represents one or more combinations of LUNAME, authorization ID, and application plan name. Rows in this table can be inserted, updated, and deleted.
SYSAUXRELS	Contains one row for each auxiliary table created for a LOB column. A base table space that is partitioned must have one auxiliary table for each partition of each LOB column.
SYSCHECKDEP	Contains one row for each reference to a column in a table check constraint.
SYSCHECKS	Contains one row for each table-check constraint.
SYSCHECKS2	Contains one row for each table-check constraint created in or after version 7.
SYSCOLAUTH	Records the UPDATE or REFERENCES privileges that are held by users on individual columns of a table or view.
SYSCOLDIST	Contains one or more rows for the first key column of an index key. Rows in this table can be inserted, updated, and deleted.
SYSCOLDIST_HIST	Contains rows from SYSCOLDIST. Whenever rows are added or changed in SYSCOLDIST, the rows are also written to the new history table. Rows in this table can be inserted, updated, and deleted.
SYSCOLDISTSTATS	Contains zero or more rows per partition for the first key column of a partitioning index or DPSI (Data Partitioned Secondary Index). Rows are inserted when RUNSTATS scans index partitions of the partitioning index. No row is inserted if the index is nonpartitioning. Rows in this table can be inserted, updated, and deleted.
SYSCOLSTATS	Contains partition statistics for selected columns. For each column, a row exists for each partition in the table. Rows are inserted when RUNSTATS collects either indexed column statistics or nonindexed column statistics for a partitioned table space. No row is inserted if the table space is nonpartitioned. Rows in this table can be inserted, updated, and deleted.
SYSCOLUMNS	Contains one row for every column of each table and view.
SYSCOLUMNS_HIST	Contains rows from SYSCOLUMNS. Whenever rows are added or changed in SYSCOLUMNS, the rows are also written to the new history table. Rows in this table can be inserted, updated, and deleted.
SYSCONSTDEP	Records dependencies on check constraints or user-defined defaults for a column.
SYSCOPY	Contains information needed for recovery.
SYSDATABASE	Contains one row for each database, except for database DSNDB01.
SYSDATATYPES	Contains one row for each distinct type defined to the system.
SYSDBAUTH	Records the privileges held by users over databases.
SYSDBRM	Contains one row for each DBRM of each application plan.
SYSDUMMY1	Contains one row. The table is used for SQL statements in which a table reference is required, but the contents of the table are not important.
SYSFIELDS	Contains one row for every column that has a field procedure.
SYSFOREIGNKEYS	Contains one row for every column of every foreign key.
SYSINDEXES	Contains one row for every index.
SYSINDEXES_HIST	Contains rows from SYSINDEXES. Whenever rows are added or changed in SYSINDEXES, they are also written to the new history table. Rows in this table can be inserted, updated, and deleted.
SYSINDEXPART	Contains one row for each nonpartitioning index and one row for each partition of a partitioning index or a DPSI.
SYSINDEXPART_HIST	Contains rows from SYSINDEXPART. Whenever rows are added or changed in SYSINDEXPART, they are also written to the new history table. Rows in this table can be inserted, updated, and deleted.
SYSINDEXSTATS	Contains one row for each partition of a partitioning index. Rows in this table can be inserted, updated, and deleted.
SYSINDEXSTATS_HIST	Contains rows from SYSINDEXSTATS. Whenever rows are added or changed in SYSINDEXSTATS, they are also written to the new history table. Rows in this table can be inserted, updated, and deleted.
SYSJARCLASS_SOURCE	Auxiliary table for SYSIBMSYSCONTENTS.
SYSJARCONTENTS	Contains Java class source for installed JAR (Java Archive).
SYSJARDATA	Auxiliary table for SYSIBMSYSOBJECTS.
SYSJAROBJECTS	Contains binary large object representing the installed JAR.
SYSJAVAOPTS	Contains build options used during INSTALL_JAR.
SYSKEYCOLUSE	Contains a row for every column in a unique constraintprimary key or unique keyfrom the SYSIBM.SYSTABCONST table.
SYSKEYS	Contains one row for each column of an index key.
SYSLOBSTATS	Contains one row for each LOB table space.
SYSLOBSTATS_HIST	Contains rows from SYSLOBSTATS. Whenever rows are added or changed in SYSLOBSTATS, they are also written to the new history table. Rows in this table can be inserted, updated, and deleted.
SYSPACKAGE	Contains a row for every package.
SYSPACKAUTH	Records the privileges that users hold over packages.
SYSPACKDEP	Records the dependencies of packages on local tables, views, synonyms, table spaces, indexes and aliases, functions, and stored procedures.
SYSPACKLIST	Contains one or more rows for every local application plan bound with a package list. Each row represents a unique entry in the plan's package list.
SYSPACKSTMT	Contains one or more rows for each statement in a package.
SYSPARMS	Contains one row for each parameter of a routine or multiple rows for table parametersone for each column of the table.
SYSPKSYSTEM	Contains zero or more rows for every package. Each row for a given package represents one or more connections to an environment in which the package could be executed.
SYSPLAN	Contains one row for each application plan.
SYSPLANAUTH	Records the privileges that users hold over application plans.
SYSPLANDEP	Records the dependencies of plans on tables, views, aliases, synonyms, table spaces, indexes, functions, and stored procedures.
SYSPLSYSTEM	Contains zero or more rows for every plan. Each row for a given plan represents one or more connections to an environment in which the plan could be used.
SYSRELS	Contains one row for every referential constraint.
SYSRESAUTH	Records CREATE IN and PACKADM ON privileges for collections, USAGE privileges for distinct types, and USE privileges for buffer pools, storage groups, and table spaces.
SYSROUTINEAUTH	Records the privileges that users hold on routines. (A routine can be a user-defined function, a cast function, or a stored procedure.)
SYSROUTINES	Contains one row for every routine. (A routine can be a user-defined function, a cast function, or a stored procedure.)
SYSROUTINES_OPTS	Contains one row for each generated routine, such as one created by the DB2 Development Center tool, that records the build options for the routine. Rows in this table can be inserted, updated, and deleted.
SYSSCHEMAAUTH	Contains one or more rows for each user granted a privilege on a particular schema in the database.
SYSSEQUENCEAUTH	Records the privileges that users hold over sequences.
SYSSEQUENCES	Contains one row for each identity column.
SYSSEQUENCESDEP	Records the dependencies of identity columns on tables.
SYSSTMT	Contains one or more rows for each SQL statement of each DBRM.
SYSSTOGROUP	Contains one row for each storage group.
SYSSTRINGS	Contains information about character conversion. Each row describes a conversion from one coded character set to another.
SYSSYNONYMS	Contains one row for each synonym of a table or a view.
SYSTABAUTH	Records the privileges that users hold on tables and views.
SYSTABCONST	Contains one row for each unique constraintprimary key or unique keycreated in DB2 for OS/390 version 7 or later.
SYSTABLEPART	Contains one row for each nonpartitioned table space and one row for each partition of a partitioned table space.
SYSTABLEPART_HIST	Contains rows from SYSTABLEPART. Rows are added or changed when RUNSTATS collects history statistics. Rows in this table can be inserted, updated, and deleted.
SYSTABLES	Contains one row for each table, view, or alias.
SYSTABLES_HIST	Contains rows from SYSTABLES. Rows are added or changed when RUNSTATS collects history statistics. Rows in this table can be inserted, updated, and deleted.
SYSTABLESPACE	Contains one row for each table space.
SYSTABSTATS	Contains one row for each partition of a partitioned table space. Rows in this table can be inserted, updated, and deleted.
SYSTABSTATS_HIST	Contains rows from SYSTABSTATS. Rows are added or changed when RUNSTATS collects history statistics. Rows in this table can be inserted, updated, and deleted.
SYSTRIGGERS	Contains one row for each trigger.
SYSUSERAUTH	Records the system privileges that users hold.
SYSVIEWDEP	Records the dependencies of views on tables, functions, and other views.
SYSVIEWS	Contains one or more rows for each view.
SYSVOLUMES	Contains one row for each volume of each storage group.
USERNAMES	Uses each row in the table to carry out one of the following operations: Outbound ID translation Inbound ID translation and "come from" checking Rows in this table can be inserted, updated, and deleted.

Catalog Consistency Queries

Consistency queries can be executed as part of the migration process to ensure that the data in the catalog is correct. These queries are found in the data set prefix.SDSNSAMP(DSNTESQ). These queries test such logical relationships as ensuring that all indexes are created on tables that exist.

The SQL statements can be executed from SPUFI or from a dynamic SQL program, such as DSNTEP2. The queries can be executed on the catalog tables or on copies of the catalog. RUNSTATS should be run on the catalog or the copies to ensure the best performance. In some cases, the queries will perform better when executed on the copies, using the extra indexes as defined for some of the tables.

Following is an example of a catalog consistency query that checks whether all table spaces belong to a defined database. This query will find all the SYSTABLESPACE databases that do not have corresponding rows in SYSDATABASE. The desiredexpectedresult is to have no rows returned.

 SELECT DBNAME, NAME    FROM SYSIBM.SYSTABLESPACE TS    WHERE NOT EXISTS      (SELECT *         FROM SYSIBM.SYSDATABASE DB         WHERE DB.NAME = TS.DBNAME); 

DB2 Directory

The DB2 directory is used to store information about the operation and housekeeping of the DB2 environment. This directory, unlike the DB2 catalog, cannot be accessed by using SQL. The DB2 directory contains information required to start DB2; activities and utilities in the DB2 environment do the updating and deleting of table entries in the DB2 directory. The DB2 directory contains five tables: a description of each is given in Table 2-5.

Table 2-5. DB2 Directory Tables

Directory Table	Information Contents
SPT01	Referred to as the skeleton package table (SKPT), this table contains information about the access paths and the internal form of the SQL for a package at bind time. Entries are made into this table during bind time (BIND PACKAGE), and entries are deleted when a package is freed (FREE PACKAGE). This table is loaded into memory at execution time, along with the SCT02 table described next.
SCT02	Referred to as the skeleton cursor table (SKCT), this table contains information about access paths and the internal form of the SQL for an application plan. Entries in this table are made when a plan is bound (BIND PLAN) and deleted when a plan is freed (FREE PLAN). This table is also loaded into memory at execution time.
DBD01	Information about DBDs (database descriptors), which are internal control blocks, is kept in this table. Each DB2 database has one DBD for its objects: table spaces, indexes, tables, referential integrity constraints, and check constraints. Updates to this table are made when a database is created or updated. This information is accessed by DB2 in place of continually using the DB2 catalog, permitting faster, more efficient access to this information. The information in the DBD01 directory table is also contained in the DB2 catalog.
SYSLGRNX	Referred to as the log range table, this table contains information from the DB2 logs about the RBA (relative byte address) range for updates. This allows DB2 to efficiently find the RBAs needed from the DB2 logs for recovery purposes. A row is inserted every time a table space or a partition is opened or updated and is updated when the object is closed.
SYSUTILX	This system utilities table stores information about the execution of DB2 utilities, including the status and the steps during execution. This information is used when a utility needs to be restarted. Information in this table is added when a utility is started, and the entry is removed when the execution has ended.